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Saucony's Freedom ISO reviewed by Chris Hough


Is this the best running shoe Saucony have ever produced?



The stats.


  • The first ever full-length EVERUN midsole
  • EVERUN Topsole construction for enhanced energy return and continuous cushioning throughout the run
  • Engineered stretch mesh upper for a dynamic, lightweight fit
  • ISOFIT creates a dynamic fit system by adapting to the shape and motion of the runner’s foot
  • Streamlined Support Frame for the ideal heel fit and hold
  • Highly durable TRI-FLEX crystal rubber outsole


  • Pronation: None
  • Cushion: Plush
  • Construction Type: Neutral
  • Surface: Road, Track
  • Arch: High, Normal (Mid)
  • Water Resistant: No
  • Water Proof: No
  • Offset: 4mm
  • Heel: 19mm/Forefoot: 15mm
  • Weight: 9.0 oz. | 255 g.

The Facts:

Okay, EVERUN's been around since the introduction of the Saucony Triumph ISO 2, back in 2015.  At first featured in small amounts, it served as crash pads and topsoles, in order to enhance the shoes.  The super bouncy, mega resilient material was a revolution to some, while others mourned the loss of a familiar feel in their 'weapon of choice'. 

As a potential midsole material in its own right - it remains to be seen whether or not it can prove as worthy as the advanced EVA options from the last few years.

One thing's for sure.  It's different.


Created by forcing hundreds of tiny balls of E-TPU Polymer together in a mould and steaming at high pressure - the EVERUN midsole is produced in the same way they make Polystyrene cups, but the material itself is far more resilient than that.  Far more resilient than most EVA in fact.  It returns to its intended shape very quickly when squashed.  It doesn't suffer when exposed to extreme temperatures either.  It will therefore last a very long time without degrading.  All very positive.

The question then, is will this directly benefit the runner?


First Impression.

In practice, there were are a few things that struck me immediately in the Freedom ISO.   First was how shallow it is.  I stayed inside the shoe, but it sits a little lower around the heel than most I've had on in recent years.  Far better than aggravating the ankle joint, or rubbing on the ankle bone the way some shoes can.  But low all the same. 

Then there's the comfort on my foot.  I'll stress this point....  


So that's a big box ticked.  Along with the low cut heel construction, there's the ISO Fit upper.  Here, another big tick.  The elastic sock around the foot simply disappears when on.  Thanks to the bands around the midfoot, the upper adapts and conforms to the shape and volume of the foot.  I forget that I'm wearing them.  Seriously. 

There's also a subtle support frame at the rear of the shoe, designed to hold the heel in place.  It's the only thing that differs from the soft, sock like constriction everywhere else and thankfully, it too never feels obvious while on.

Third was the feeling under foot.  It felt soft, but not so much that it squashed flat.  I rode on top of it, in the way I might if I stood on a very full water balloon.  Squidgy, but only to a point.  The eventual resistance (when the material compressed as far as it could) then turned into a little bit of a wobble.

Saucony have still included a full length topsole here, also constructed from EVERUN and added it between the midsole and the insole, for added cushioning.  I think this might be a tad overkill.  'Too much of a good thing'.  The result feels like these layers have too much wriggle room while you apply force from above, the layers can't help but shift on top of one another, while each is still able to twist and collapse quite freely.

So for me, running on the Freedom ISO becomes a challenge over uneven ground or while tired.

Think - sofa cushions on top of one another and trying to balance on the top.

Regardless of whether it could do with a tad less 'boing', if I landed squarely on the shoe, nailing my form and remaining completely neutral, I was riding well and feeling fast.



Long Term.

Freedom ISO is truly unlike any Saucony shoe of the past.  But I believe they may have provided too much of a good thing with the introduction of a fully formed E-TPU Midsole.  It will appeal to those who enjoy comfort in an everyday shoe.  It'll work brillaintly on people who run strong and neutral or not at all.  Those who wish to treat it as an all round trainer/racer and run in nothing else are likely to encounter issues with instability and loss of control.  There's the possibility of injury if not supremely stable on this shoe.

Of course, if I run in only one shoe all of the time and it doesn't suit me perfectly (or my chosen environment) - I'll end up falling out with it.  But I've a 'tool box' of shoes at home.  I run an average of 50 miles per week when everything's going according to plan, sometimes more. 

I can chop and change between shoes according to how I feel, or how well I'm doing.  At the time of writing this review for example, I'd run my 3.75 miles to work in a zero drop (flat) shoe with practically no midsole to speak of and followed it with a session of S&C/S (strength & conditioning/stability).  So I can expect to feel a little weaker than I might otherwise, fatigued also.  I won't tip from the shoe, because there's nowhere to go, but I'll feel the impact as soon as I lose the ability to land correctly and handle the load through my lower leg in particular.

Why mention this?  Well, for many - there will inevitably come a point when they're feeling a little unstable, even if they're normally strong as an Ox.  No concern for those who also have plenty of choice, but if you're the type who selects a single shoe for almost constant use until it wears out, then replaces it for more of the same.  Perhaps doing any and every type of thing there is to do in a running shoe and still not willing to expand the collection.  The Freedom is going to prove a little unruly at times.

That EVERUN midsole, for all of its wear resistance and bounce, never feels so trustworthy that I can really just switch off and run on autopilot.  I'm relatively strong.  I run neutral.  I have what I'm told is pretty good form.  Yet there's been the odd step when I've kicked myself, taken a near miss turn of the ankle or suddenly become very aware that I'm failing to move correctly due to fatigue.

True, you shouldn't really push your luck if this is happening, but we all do on occasion.  I usually get away with flogging myself to death on the odd run home, because I have an appointment or I stubbornly refuse to admit defeat.

The Freedom ISO will provide comfort in spades and is at the cutting edge of design and innovation.  It looks great and is really very effective when used correctly, on the right kind of feet.  It grips the floor brilliantly, thanks to the one piece Crystal Rubber Outsole.  In damp or dirty areas, where mud and silt have covered your path, there's plenty of traction and I haven't slipped once so far.  Pretty good for the UK and its ever wet conditions.


If you lack strength and already suffer niggles in demanding, or minimal footwear, then the Freedom ISO should be approached with caution.

I think with this, more than with any other shoe we've stocked at Accelerate, the important thing would be to have a try on and see what the results are.  Have us assess its fitness for purpose and above all, decide how you feel it works for you.

I love the feel of this shoe.  I love the comfort.  I enjoy wearing it as an all day 'shop shoe'. 

While I'm fresh and in complete control of what I'm doing, it's a joy to run in. 

But when I attempt to run hard, or without constant scrutiny, I find that there can be regular wake up calls, due to instability in that flexible midsole. 

The multiple layers of flexible, bouncy material could destabilise your feet, testing even the strongest runner and as we've found between us in the store (via our treadmill and store front) it can sometimes look a little lateral on those who use the outside edge of their feet in particular.

If you're concerned that this might be the case with you and your running - it's always worth popping into a shop like ours and having us provide you with a test run, along with some assessment of your strength and running form.

There are already so many fantastic shoes within the Saucony range, it's far from necessary to opt for the latest one on principle.



So who should buy the Freedom ISO? 

Anyone wishing for the latest thing, this is it. 

People who run slow and steady, but still wish for a more minimal shoe than their usual chunky high mileage option, might find that the Freedom ISO affords them a very hard wearing shoe that still looks super stylish and in time will provide plenty of well placed speed if used correctly. 

Anyone who (like me) ownes enough shoes already, that they can pick and choose between them, using the correct shoe for any particular day and in doing so avoid mistakes through over working, when the environment or their energy levels threaten to undermine the desire to run forever.

Those with really imobile joints and a need for as much movement as they can muster - look no further. 

And anyone who likes a cool looking 'all day - every day' casual shoe to show off in.  Obviously.

Purchase Freedom ISO


By Chris Hough.


Chris is supported by Team Accelerate

He blogs as Houghboy

He tweets as @HoughboyRunner

Monday 20th of February 2017

Accelerate Lifestyle Limited

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